SEGV_MAPERR = C.SEGV_MAPERR
	SEGV_ACCERR = C.SEGV_ACCERR

	ITIMER_REAL    = C.ITIMER_REAL
	ITIMER_VIRTUAL = C.ITIMER_VIRTUAL
	ITIMER_PROF    = C.ITIMER_PROF

	O_RDONLY  = C.O_RDONLY
	O_CLOEXEC = C.O_CLOEXEC
)

type Fpreg C.struct__fpreg
type Fpxreg C.struct__fpxreg
type Xmmreg C.struct__xmmreg
type Fpstate C.struct__fpstate
type Timespec C.struct_timespec
type Timeval C.struct_timeval

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build js && wasm

package os

// supportsCloseOnExec reports whether the platform supports the
// O_CLOEXEC flag.

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

//go:build aix || darwin

package syscall

// forkExecPipe opens a pipe and non-atomically sets O_CLOEXEC on both file
// descriptors.
func forkExecPipe(p []int) error {
	err := Pipe(p)
	if err != nil {
		return err
	}
	_, err = fcntl(p[0], F_SETFD, FD_CLOEXEC)
	if err != nil {
		return err
	}

	FORK_WAITPID   = C.FORK_WAITPID

	MAXHOSTNAMELEN = C.MAXHOSTNAMELEN

	O_WRONLY   = C.O_WRONLY
	O_NONBLOCK = C.O_NONBLOCK
	O_CREAT    = C.O_CREAT
	O_TRUNC    = C.O_TRUNC
	O_CLOEXEC  = C.O_CLOEXEC

	POLLIN  = C.POLLIN
	POLLOUT = C.POLLOUT
	POLLHUP = C.POLLHUP
	POLLERR = C.POLLERR

	PORT_SOURCE_FD    = C.PORT_SOURCE_FD
	PORT_SOURCE_ALERT = C.PORT_SOURCE_ALERT

const (
	EINTR     = C.EINTR
	EFAULT    = C.EFAULT
	EAGAIN    = C.EAGAIN
	ETIMEDOUT = C.ETIMEDOUT

	O_WRONLY   = C.O_WRONLY
	O_NONBLOCK = C.O_NONBLOCK
	O_CREAT    = C.O_CREAT
	O_TRUNC    = C.O_TRUNC
	O_CLOEXEC  = C.O_CLOEXEC

	PROT_NONE  = C.PROT_NONE
	PROT_READ  = C.PROT_READ
	PROT_WRITE = C.PROT_WRITE
	PROT_EXEC  = C.PROT_EXEC

	MAP_ANON    = C.MAP_ANON
	MAP_SHARED  = C.MAP_SHARED
	MAP_PRIVATE = C.MAP_PRIVATE

// license that can be found in the LICENSE file.

package syscall

// Plan 9 Constants

// Open modes
const (
	O_RDONLY  = 0
	O_WRONLY  = 1
	O_RDWR    = 2
	O_TRUNC   = 16
	O_CLOEXEC = 32
	O_EXCL    = 0x1000
)

// Bind flags
const (
	MORDER  = 0x0003 // mask for bits defining order of mounting
	MREPL   = 0x0000 // mount replaces object

import "golang.org/x/sys/unix"

// Acquire acquires a lock on a file for the duration of the process. This method
// is reentrant.
func Acquire(path string) error {
	fd, err := unix.Open(path, unix.O_CREAT|unix.O_RDWR|unix.O_CLOEXEC, 0600)
	if err != nil {
		return err
	}

	// We don't need to close the fd since we should hold
	// it until the process exits.

	return unix.Flock(fd, unix.LOCK_EX)

	var err error
	watchfd, err = unix.Open(fmt.Sprintf("%s/%s", path, attribute), unix.O_RDONLY|unix.O_CLOEXEC, 0)
	if err != nil {
		return nil, err
	}
	defer unix.Close(watchfd)
	controlfd, err = unix.Open(fmt.Sprintf("%s/cgroup.event_control", path), unix.O_WRONLY|unix.O_CLOEXEC, 0)
	if err != nil {
		return nil, err
	}
	defer unix.Close(controlfd)
	eventfd, err = unix.Eventfd(0, unix.EFD_CLOEXEC)

		if err != nil {
			return fmt.Errorf("cannot create directory %s: %s", currentPath, err)
		}
		// Dive into the created directory
		childFD, err = syscall.Openat(parentFD, dir, nofollowFlags|unix.O_CLOEXEC, 0)
		if err != nil {
			return fmt.Errorf("cannot open %s: %s", currentPath, err)
		}
		// We can be sure that childFD is safe to use. It could be changed
		// by user after Mkdirat() and before Openat(), however:

	// (The Linux kernel guarantees that it is closed on an EINTR error.)
	return CloseFunc(fd)
}

// dupCloseOnExecOld is the traditional way to dup an fd and
// set its O_CLOEXEC bit, using two system calls.
func dupCloseOnExecOld(fd int) (int, string, error) {
	syscall.ForkLock.RLock()
	defer syscall.ForkLock.RUnlock()
	newfd, err := syscall.Dup(fd)
	if err != nil {
		return -1, "dup", err